When a killer whale appeared in the perfect spot, just below the water's surface as a low November sun broke through to its underwater world, Audun Rikardsen knew he only had one chance to get the shot. The next day, the sun would set for the last time that year in Tromsø, and two months of Polar Night, with 24-hour darkness, would follow.

Being a scientist, Audun had planned his shot down to the last detail. He wanted the sun to be as low on the horizon as possible, with waves scattering the sunlight, and a whale just below the water's surface so he could frame it with perfect rays of light in the background. It wasn't just for his own satisfaction that he needed all these things to coincide; a film crew from one of Norway's main TV news channels was shooting a documentary about Audun's whale photography, and they needed to get their footage before the two months of darkness began.

"The whales arrive because of the herring that comes into the fjords in the beginning of November," says Audun, "and I had a window of about a week and a half to get the picture before the sun would disappear on the 15th. But I also needed perfect conditions, with the light, the waves and of course the whale, and that only happened on the very last day."

Scientific settings

On this day, the whales were circling near a fishing boat, so Audun jumped in with a snorkelling mask to take a look. Because the air temperature was below zero, Audun wore a drysuit with several layers of warm clothes underneath. That made it difficult to dive, so he swam near the water's surface and submerged the camera and its housing a couple of metres down on a pole. He couldn't see what the camera was seeing, but prior to the shoot he had set the focus manually on the exact spot where he wanted the whale to appear. He had also tested a variety of settings and lenses to ensure that he had the right setup.

Do you own Canon kit?

It was important to Audun that the whale would take up enough space in the composition, and that the sun wouldn't appear too far away in the distance. He didn't want to use his widest lens, but he still wanted a wide-angle perspective. He decided on the Canon EF 16-35mm f/2.8L III USM, an L-series ultra-wide angle zoom lens that is designed to perform flawlessly in low-light conditions. "Often, 16mm is wide enough to get the super-wide look, plus you still have the option to zoom in," he says. "The lens is really sharp, and the maximum aperture of f/2.8 gives you a lot of possibilities in low-light conditions."

Because of the low level of light, Audun had to use a slower shutter speed than he was comfortable with, choosing 1/200 sec. "I would have preferred to use a faster shutter speed because I had to freeze the sun's rays, which were moving quite quickly. If the shutter speed is too slow [for underwater photographs like this, near the surface], you'll still capture the sun's rays, but they will be less defined. I also wanted some depth of field in case the whale moved closer to me, so I set the aperture at f/6.3, reducing the light coming in," he explains.

"If I had chosen the lens's maximum aperture of f/2.8, the depth of field would have been very narrow. I used a manual focus that I set before I took the picture, so the margin for error [at f/2.8] would have been too great," he adds.

Visual deception

As well as selecting the right settings, one of the biggest challenges for this photograph was using the correct camera angle to get a strong composition. Using a diving mask, it is easy to be tricked by the distorted perspective underwater; for example, when you dip an object into water, the part that's under the surface looks like it has broken off. This effect also applies to the positioning of the camera. "If you place the camera at an angle that you think is right, it's usually too high up," Audun says. "I know that, so I always place the camera a little further down than I think it should be, and that gives me the ideal angle."

Having prepared everything for the perfect shot, Audun waited patiently for a whale to follow his plan. "A few whales came up to me, and this one came from below to check me out. Then it went up to breathe at the surface, just at the right position against the sun," he says. He set off a continuous burst on the Canon EOS 5D Mark III and captured a sequence of unique shots that fulfilled his creative vision.

"It could only have happened at that moment, at that time of the year when the sun is really low on the horizon," he says. "You can get scattered sun rays even with a high sun, but the rays usually won't be this golden; the sun has to be very low on the horizon for that to happen. And if the waves hadn't been there, I wouldn't have captured as many rays because they wouldn't have penetrated the surface. That's why I called this photograph Underwater Symphony – everything came together at the right moment."

Lenses

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This professional-quality standard zoom lens offers outstanding image sharpness and a robust L-series build. Its constant f/2.8 aperture enables you to take superb photos even in low light, and to control depth of field with ease.